"When people come to Pizzaiolo and say, 'I don't eat wheat or cheese,' I'm like, 'Why did you come to a pizzeria?' " Hallowell says.

It's a question chefs are asking more and more as diners become increasingly picky about what they want - or don't want - on their plates.

No gluten. No salt. No dairy. No wheat.

No peanuts. No seeds. No fat.

Whether it's someone following a vegan or macrobiotic diet, someone allergic to wheat or nuts, or someone who simply doesn't like mushrooms or eggs, there's a new wave of special requests being made that go far beyond leaving the salad dressing on the side.

"It's like a puzzle," says Andrew Generalao, La Mar's general manager. "You have to try to find the right fit, and sometimes we pull it off with great things. A lot of times, it's just not that exciting."

Like most in the restaurant industry, Generalao wants to wow his customers. But trying to make ceviche without cilantro or jalapenos is like ordering macaroni and cheese without the cheese. Though the dish still might be perfectly good, its essence has been stripped away.

Still, Generalao added three vegan items to his seafood-heavy menu shortly after opening, and says he's happy to accommodate the special requests he gets.

But in an era where cafegoers order split-shot soy mocha lattes with sugar-free vanilla, light foam, no whip - and extra hot, please - restaurantgoers are tailoring even fixed menus to their taste buds.

Skenes offers one nine-course meal at Saison, and though he asks that the menu stay the menu, he still gets several special requests per week.

"We don't rule over the kitchen with an iron fist and say, 'No soup for you,' " Skenes says. "But we do it on a case-by-case basis.

"The other day, we had someone who didn't eat shellfish, didn't eat fish, didn't eat dairy, didn't eat lamb. And on the menu, we had shellfish, we had fish, we had lamb. And they also didn't eat gluten or wheat.

"So that was pretty much impossible. We just couldn't do it."

Skenes says it's mostly a matter of staffing and resources - it's too much of a strain on the small kitchen to constantly handle special requests.

Daniel Patterson, chef-owner at San Francisco's four-star Coi, can empathize. While Patterson, who also serves a fixed menu, will accommodate all food allergies and aversions with advance notice, he knows that isn't always possible at smaller, specialized venues.

"People want more and more for less and less, and they're trying to do that, but these special requests are something they're not equipped to do, and it has a trickle-down effect (on service)," he says.

Patterson's biggest challenge to date at Coi? Serving raw foodists. For that, he researched new methods of preparation, and some elements of raw cooking - such as soaking organic almonds in water, peeling off their skins and pureeing them with wheatgrass - have shown up in recent dishes.